Specifies whether the input file is to be sorted before being
    loaded into an indexed file. The sort is done according to the
    primary key of the output file.
    Format
      /SORT [=FORCE]  (DEFAULT)
      /NOSORT
    Two procedures can improve the sort performance:
    o  Increasing the size of the working set for the duration of the
       sort.
    o  Placing the input file, the output file, and the temporary
       work files on separate disk devices.
    By default, when there is a single indexed input file with
    the same primary key definition as the output file, CONVERT
    does not perform a sort of the primary key. If you specify the
    keyword FORCE, it forces a sorting operation for the primary key.
    If you specify /NOSORT with /FAST_LOAD, only the SORT of the
    primary key is disabled. Alternate or secondary keys are
    always sorted. The /NOSORT qualifier is useful when you know
    the input file is already in primary key order.